Sharon Stone in Harper's Bazaar magazine. Photo / Instagram.com via @Harpersbazaarus

Sharon Stone has posed naked in the September issue of Harper's Bazaar at 57 years of age.

Stone said in her interview to the US magazine that she questioned herself asking "what really is sexy?".

The Casino star said: "I'm not trying to be the best-looking broad in the world. At a certain point you start asking yourself, 'What really is sexy?' It's not just the elevation of your boobs. It's being present and having fun and liking yourself enough to like the person that's with you. If I believed that sexy was trying to be who I was when I did Basic Instinct, then we'd all be having a hard day today."

Despite being confident enough to pose nude for the publication, Stone quipped thinking her butt "looks like a bag of flapjacks."

Sharon Stone goes completely nude and reveals ALL in BAZAAR's September issue:

— Harper's Bazaar (@harpersbazaarus) August 14, 2015

The 57-year-old actress went on to reveal that she felt like her "entire DNA changed" after suffering a brain haemorrhage in 2001. She admitted it took her years to fully recover from the medical emergency and she is still feeling the effects of brain damage.

Stone said: "It almost feels like my entire DNA changed. My brain isn't sitting where it used to, my body type changed, and even my food allergies are different."

But the blonde beauty, who once feared she would never be able to read or speak again, believes the experience taught her a lot.

"I became more emotionally intelligent. I chose to work very hard to open up other parts of my mind. Now I'm stronger. And I can be abrasively direct. That scares people, but I think that's not my problem. It's like, I have brain damage; you'll just have to deal with it."

- Bang! Showbiz